2 * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3 * user-supplied information to configure own IP address and routes.
5 * Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7 * Derived from network configuration code in fs/nfs/nfsroot.c,
8 * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
10 * BOOTP rewritten to construct and analyse packets itself instead
11 * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
12 * -- MJ, December 1998
14 * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
15 * initialization scheme.
16 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
18 * DHCP support added. To users this looks like a whole separate
19 * protocol, but we know it's just a bag on the side of BOOTP.
20 * -- Chip Salzenberg <chip@valinux.com>, May 2000
22 * Ported DHCP support from 2.2.16 to 2.4.0-test4
23 * -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
25 * Merged changes from 2.2.19 into 2.4.3
26 * -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
28 * Multiple Nameservers in /proc/net/pnp
29 * -- Josef Siemes <jsiemes@web.de>, Aug 2002
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/jiffies.h>
36 #include <linux/random.h>
37 #include <linux/init.h>
38 #include <linux/utsname.h>
41 #include <linux/inet.h>
42 #include <linux/inetdevice.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
47 #include <linux/socket.h>
48 #include <linux/route.h>
49 #include <linux/udp.h>
50 #include <linux/proc_fs.h>
51 #include <linux/seq_file.h>
52 #include <linux/major.h>
53 #include <linux/root_dev.h>
54 #include <linux/delay.h>
55 #include <linux/nfs_fs.h>
56 #include <linux/slab.h>
57 #include <linux/export.h>
58 #include <net/net_namespace.h>
62 #include <net/ipconfig.h>
63 #include <net/route.h>
65 #include <linux/uaccess.h>
66 #include <net/checksum.h>
67 #include <asm/processor.h>
69 #if defined(CONFIG_IP_PNP_DHCP)
72 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
73 #define IPCONFIG_BOOTP
75 #if defined(CONFIG_IP_PNP_RARP)
78 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
79 #define IPCONFIG_DYNAMIC
82 /* Define the friendly delay before and after opening net devices */
83 #define CONF_POST_OPEN 10 /* After opening: 10 msecs */
84 #define CONF_CARRIER_TIMEOUT 120000 /* Wait for carrier timeout */
86 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
87 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
88 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
89 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
90 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
91 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
92 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
93 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
94 - '3' from resolv.h */
96 #define NONE cpu_to_be32(INADDR_NONE)
97 #define ANY cpu_to_be32(INADDR_ANY)
100 * Public IP configuration
103 /* This is used by platforms which might be able to set the ipconfig
104 * variables using firmware environment vars. If this is set, it will
105 * ignore such firmware variables.
107 int ic_set_manually __initdata
= 0; /* IPconfig parameters set manually */
109 static int ic_enable __initdata
; /* IP config enabled? */
111 /* Protocol choice */
112 int ic_proto_enabled __initdata
= 0
113 #ifdef IPCONFIG_BOOTP
116 #ifdef CONFIG_IP_PNP_DHCP
124 static int ic_host_name_set __initdata
; /* Host name set by us? */
126 __be32 ic_myaddr
= NONE
; /* My IP address */
127 static __be32 ic_netmask
= NONE
; /* Netmask for local subnet */
128 __be32 ic_gateway
= NONE
; /* Gateway IP address */
130 #ifdef IPCONFIG_DYNAMIC
131 static __be32 ic_addrservaddr
= NONE
; /* IP Address of the IP addresses'server */
134 __be32 ic_servaddr
= NONE
; /* Boot server IP address */
136 __be32 root_server_addr
= NONE
; /* Address of NFS server */
137 u8 root_server_path
[256] = { 0, }; /* Path to mount as root */
139 /* vendor class identifier */
140 static char vendor_class_identifier
[253] __initdata
;
142 #if defined(CONFIG_IP_PNP_DHCP)
143 static char dhcp_client_identifier
[253] __initdata
;
146 /* Persistent data: */
148 #ifdef IPCONFIG_DYNAMIC
149 static int ic_proto_used
; /* Protocol used, if any */
151 #define ic_proto_used 0
153 static __be32 ic_nameservers
[CONF_NAMESERVERS_MAX
]; /* DNS Server IP addresses */
154 static u8 ic_domain
[64]; /* DNS (not NIS) domain name */
160 /* Name of user-selected boot device */
161 static char user_dev_name
[IFNAMSIZ
] __initdata
= { 0, };
163 /* Protocols supported by available interfaces */
164 static int ic_proto_have_if __initdata
;
166 /* MTU for boot device */
167 static int ic_dev_mtu __initdata
;
169 #ifdef IPCONFIG_DYNAMIC
170 static DEFINE_SPINLOCK(ic_recv_lock
);
171 static volatile int ic_got_reply __initdata
; /* Proto(s) that replied */
174 static int ic_dhcp_msgtype __initdata
; /* DHCP msg type received */
183 struct ic_device
*next
;
184 struct net_device
*dev
;
185 unsigned short flags
;
190 static struct ic_device
*ic_first_dev __initdata
; /* List of open device */
191 static struct ic_device
*ic_dev __initdata
; /* Selected device */
193 static bool __init
ic_is_init_dev(struct net_device
*dev
)
195 if (dev
->flags
& IFF_LOOPBACK
)
197 return user_dev_name
[0] ? !strcmp(dev
->name
, user_dev_name
) :
198 (!(dev
->flags
& IFF_LOOPBACK
) &&
199 (dev
->flags
& (IFF_POINTOPOINT
|IFF_BROADCAST
)) &&
200 strncmp(dev
->name
, "dummy", 5));
203 static int __init
ic_open_devs(void)
205 struct ic_device
*d
, **last
;
206 struct net_device
*dev
;
207 unsigned short oflags
;
208 unsigned long start
, next_msg
;
210 last
= &ic_first_dev
;
213 /* bring loopback and DSA master network devices up first */
214 for_each_netdev(&init_net
, dev
) {
215 if (!(dev
->flags
& IFF_LOOPBACK
) && !netdev_uses_dsa(dev
))
217 if (dev_change_flags(dev
, dev
->flags
| IFF_UP
) < 0)
218 pr_err("IP-Config: Failed to open %s\n", dev
->name
);
221 for_each_netdev(&init_net
, dev
) {
222 if (ic_is_init_dev(dev
)) {
227 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
228 dev
->name
, dev
->mtu
);
229 if (!(dev
->flags
& IFF_NOARP
))
231 able
&= ic_proto_enabled
;
232 if (ic_proto_enabled
&& !able
)
235 if (dev_change_flags(dev
, oflags
| IFF_UP
) < 0) {
236 pr_err("IP-Config: Failed to open %s\n",
240 if (!(d
= kmalloc(sizeof(struct ic_device
), GFP_KERNEL
))) {
250 get_random_bytes(&d
->xid
, sizeof(__be32
));
253 ic_proto_have_if
|= able
;
254 pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
255 dev
->name
, able
, d
->xid
);
259 /* no point in waiting if we could not bring up at least one device */
263 /* wait for a carrier on at least one device */
265 next_msg
= start
+ msecs_to_jiffies(CONF_CARRIER_TIMEOUT
/12);
266 while (time_before(jiffies
, start
+
267 msecs_to_jiffies(CONF_CARRIER_TIMEOUT
))) {
270 for_each_netdev(&init_net
, dev
)
271 if (ic_is_init_dev(dev
) && netif_carrier_ok(dev
))
276 if (time_before(jiffies
, next_msg
))
279 elapsed
= jiffies_to_msecs(jiffies
- start
);
280 wait
= (CONF_CARRIER_TIMEOUT
- elapsed
+ 500)/1000;
281 pr_info("Waiting up to %d more seconds for network.\n", wait
);
282 next_msg
= jiffies
+ msecs_to_jiffies(CONF_CARRIER_TIMEOUT
/12);
290 if (user_dev_name
[0])
291 pr_err("IP-Config: Device `%s' not found\n",
294 pr_err("IP-Config: No network devices available\n");
300 static void __init
ic_close_devs(void)
302 struct ic_device
*d
, *next
;
303 struct net_device
*dev
;
310 if (d
!= ic_dev
&& !netdev_uses_dsa(dev
)) {
311 pr_debug("IP-Config: Downing %s\n", dev
->name
);
312 dev_change_flags(dev
, d
->flags
);
320 * Interface to various network functions.
324 set_sockaddr(struct sockaddr_in
*sin
, __be32 addr
, __be16 port
)
326 sin
->sin_family
= AF_INET
;
327 sin
->sin_addr
.s_addr
= addr
;
328 sin
->sin_port
= port
;
331 static int __init
ic_devinet_ioctl(unsigned int cmd
, struct ifreq
*arg
)
335 mm_segment_t oldfs
= get_fs();
337 res
= devinet_ioctl(&init_net
, cmd
, (struct ifreq __user
*) arg
);
342 static int __init
ic_dev_ioctl(unsigned int cmd
, struct ifreq
*arg
)
346 mm_segment_t oldfs
= get_fs();
348 res
= dev_ioctl(&init_net
, cmd
, (struct ifreq __user
*) arg
);
353 static int __init
ic_route_ioctl(unsigned int cmd
, struct rtentry
*arg
)
357 mm_segment_t oldfs
= get_fs();
359 res
= ip_rt_ioctl(&init_net
, cmd
, (void __user
*) arg
);
365 * Set up interface addresses and routes.
368 static int __init
ic_setup_if(void)
371 struct sockaddr_in
*sin
= (void *) &ir
.ifr_ifru
.ifru_addr
;
374 memset(&ir
, 0, sizeof(ir
));
375 strcpy(ir
.ifr_ifrn
.ifrn_name
, ic_dev
->dev
->name
);
376 set_sockaddr(sin
, ic_myaddr
, 0);
377 if ((err
= ic_devinet_ioctl(SIOCSIFADDR
, &ir
)) < 0) {
378 pr_err("IP-Config: Unable to set interface address (%d)\n",
382 set_sockaddr(sin
, ic_netmask
, 0);
383 if ((err
= ic_devinet_ioctl(SIOCSIFNETMASK
, &ir
)) < 0) {
384 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
388 set_sockaddr(sin
, ic_myaddr
| ~ic_netmask
, 0);
389 if ((err
= ic_devinet_ioctl(SIOCSIFBRDADDR
, &ir
)) < 0) {
390 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
394 /* Handle the case where we need non-standard MTU on the boot link (a network
395 * using jumbo frames, for instance). If we can't set the mtu, don't error
396 * out, we'll try to muddle along.
398 if (ic_dev_mtu
!= 0) {
399 strcpy(ir
.ifr_name
, ic_dev
->dev
->name
);
400 ir
.ifr_mtu
= ic_dev_mtu
;
401 if ((err
= ic_dev_ioctl(SIOCSIFMTU
, &ir
)) < 0)
402 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
408 static int __init
ic_setup_routes(void)
410 /* No need to setup device routes, only the default route... */
412 if (ic_gateway
!= NONE
) {
416 memset(&rm
, 0, sizeof(rm
));
417 if ((ic_gateway
^ ic_myaddr
) & ic_netmask
) {
418 pr_err("IP-Config: Gateway not on directly connected network\n");
421 set_sockaddr((struct sockaddr_in
*) &rm
.rt_dst
, 0, 0);
422 set_sockaddr((struct sockaddr_in
*) &rm
.rt_genmask
, 0, 0);
423 set_sockaddr((struct sockaddr_in
*) &rm
.rt_gateway
, ic_gateway
, 0);
424 rm
.rt_flags
= RTF_UP
| RTF_GATEWAY
;
425 if ((err
= ic_route_ioctl(SIOCADDRT
, &rm
)) < 0) {
426 pr_err("IP-Config: Cannot add default route (%d)\n",
436 * Fill in default values for all missing parameters.
439 static int __init
ic_defaults(void)
442 * At this point we have no userspace running so need not
443 * claim locks on system_utsname
446 if (!ic_host_name_set
)
447 sprintf(init_utsname()->nodename
, "%pI4", &ic_myaddr
);
449 if (root_server_addr
== NONE
)
450 root_server_addr
= ic_servaddr
;
452 if (ic_netmask
== NONE
) {
453 if (IN_CLASSA(ntohl(ic_myaddr
)))
454 ic_netmask
= htonl(IN_CLASSA_NET
);
455 else if (IN_CLASSB(ntohl(ic_myaddr
)))
456 ic_netmask
= htonl(IN_CLASSB_NET
);
457 else if (IN_CLASSC(ntohl(ic_myaddr
)))
458 ic_netmask
= htonl(IN_CLASSC_NET
);
460 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
464 pr_notice("IP-Config: Guessing netmask %pI4\n",
477 static int ic_rarp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
);
479 static struct packet_type rarp_packet_type __initdata
= {
480 .type
= cpu_to_be16(ETH_P_RARP
),
481 .func
= ic_rarp_recv
,
484 static inline void __init
ic_rarp_init(void)
486 dev_add_pack(&rarp_packet_type
);
489 static inline void __init
ic_rarp_cleanup(void)
491 dev_remove_pack(&rarp_packet_type
);
495 * Process received RARP packet.
498 ic_rarp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
)
501 unsigned char *rarp_ptr
;
503 unsigned char *tha
; /* t for "target" */
506 if (!net_eq(dev_net(dev
), &init_net
))
509 skb
= skb_share_check(skb
, GFP_ATOMIC
);
513 if (!pskb_may_pull(skb
, sizeof(struct arphdr
)))
516 /* Basic sanity checks can be done without the lock. */
517 rarp
= (struct arphdr
*)skb_transport_header(skb
);
519 /* If this test doesn't pass, it's not IP, or we should
522 if (rarp
->ar_hln
!= dev
->addr_len
|| dev
->type
!= ntohs(rarp
->ar_hrd
))
525 /* If it's not a RARP reply, delete it. */
526 if (rarp
->ar_op
!= htons(ARPOP_RREPLY
))
529 /* If it's not Ethernet, delete it. */
530 if (rarp
->ar_pro
!= htons(ETH_P_IP
))
533 if (!pskb_may_pull(skb
, arp_hdr_len(dev
)))
536 /* OK, it is all there and looks valid, process... */
537 rarp
= (struct arphdr
*)skb_transport_header(skb
);
538 rarp_ptr
= (unsigned char *) (rarp
+ 1);
540 /* One reply at a time, please. */
541 spin_lock(&ic_recv_lock
);
543 /* If we already have a reply, just drop the packet */
547 /* Find the ic_device that the packet arrived on */
549 while (d
&& d
->dev
!= dev
)
552 goto drop_unlock
; /* should never happen */
554 /* Extract variable-width fields */
555 rarp_ptr
+= dev
->addr_len
;
556 memcpy(&sip
, rarp_ptr
, 4);
559 rarp_ptr
+= dev
->addr_len
;
560 memcpy(&tip
, rarp_ptr
, 4);
562 /* Discard packets which are not meant for us. */
563 if (memcmp(tha
, dev
->dev_addr
, dev
->addr_len
))
566 /* Discard packets which are not from specified server. */
567 if (ic_servaddr
!= NONE
&& ic_servaddr
!= sip
)
570 /* We have a winner! */
572 if (ic_myaddr
== NONE
)
575 ic_addrservaddr
= sip
;
576 ic_got_reply
= IC_RARP
;
579 /* Show's over. Nothing to see here. */
580 spin_unlock(&ic_recv_lock
);
583 /* Throw the packet out. */
590 * Send RARP request packet over a single interface.
592 static void __init
ic_rarp_send_if(struct ic_device
*d
)
594 struct net_device
*dev
= d
->dev
;
595 arp_send(ARPOP_RREQUEST
, ETH_P_RARP
, 0, dev
, 0, NULL
,
596 dev
->dev_addr
, dev
->dev_addr
);
601 * Predefine Nameservers
603 static inline void __init
ic_nameservers_predef(void)
607 for (i
= 0; i
< CONF_NAMESERVERS_MAX
; i
++)
608 ic_nameservers
[i
] = NONE
;
612 * DHCP/BOOTP support.
615 #ifdef IPCONFIG_BOOTP
617 struct bootp_pkt
{ /* BOOTP packet format */
618 struct iphdr iph
; /* IP header */
619 struct udphdr udph
; /* UDP header */
620 u8 op
; /* 1=request, 2=reply */
621 u8 htype
; /* HW address type */
622 u8 hlen
; /* HW address length */
623 u8 hops
; /* Used only by gateways */
624 __be32 xid
; /* Transaction ID */
625 __be16 secs
; /* Seconds since we started */
626 __be16 flags
; /* Just what it says */
627 __be32 client_ip
; /* Client's IP address if known */
628 __be32 your_ip
; /* Assigned IP address */
629 __be32 server_ip
; /* (Next, e.g. NFS) Server's IP address */
630 __be32 relay_ip
; /* IP address of BOOTP relay */
631 u8 hw_addr
[16]; /* Client's HW address */
632 u8 serv_name
[64]; /* Server host name */
633 u8 boot_file
[128]; /* Name of boot file */
634 u8 exten
[312]; /* DHCP options / BOOTP vendor extensions */
638 #define BOOTP_REQUEST 1
639 #define BOOTP_REPLY 2
641 /* DHCP message types */
642 #define DHCPDISCOVER 1
644 #define DHCPREQUEST 3
645 #define DHCPDECLINE 4
648 #define DHCPRELEASE 7
651 static int ic_bootp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
);
653 static struct packet_type bootp_packet_type __initdata
= {
654 .type
= cpu_to_be16(ETH_P_IP
),
655 .func
= ic_bootp_recv
,
659 * Initialize DHCP/BOOTP extension fields in the request.
662 static const u8 ic_bootp_cookie
[4] = { 99, 130, 83, 99 };
667 ic_dhcp_init_options(u8
*options
, struct ic_device
*d
)
669 u8 mt
= ((ic_servaddr
== NONE
)
670 ? DHCPDISCOVER
: DHCPREQUEST
);
674 pr_debug("DHCP: Sending message type %d (%s)\n", mt
, d
->dev
->name
);
676 memcpy(e
, ic_bootp_cookie
, 4); /* RFC1048 Magic Cookie */
679 *e
++ = 53; /* DHCP message type */
683 if (mt
== DHCPREQUEST
) {
684 *e
++ = 54; /* Server ID (IP address) */
686 memcpy(e
, &ic_servaddr
, 4);
689 *e
++ = 50; /* Requested IP address */
691 memcpy(e
, &ic_myaddr
, 4);
697 static const u8 ic_req_params
[] = {
699 3, /* Default gateway */
702 15, /* Domain name */
705 40, /* NIS domain name */
708 *e
++ = 55; /* Parameter request list */
709 *e
++ = sizeof(ic_req_params
);
710 memcpy(e
, ic_req_params
, sizeof(ic_req_params
));
711 e
+= sizeof(ic_req_params
);
713 if (ic_host_name_set
) {
714 *e
++ = 12; /* host-name */
715 len
= strlen(utsname()->nodename
);
717 memcpy(e
, utsname()->nodename
, len
);
720 if (*vendor_class_identifier
) {
721 pr_info("DHCP: sending class identifier \"%s\"\n",
722 vendor_class_identifier
);
723 *e
++ = 60; /* Class-identifier */
724 len
= strlen(vendor_class_identifier
);
726 memcpy(e
, vendor_class_identifier
, len
);
729 len
= strlen(dhcp_client_identifier
+ 1);
730 /* the minimum length of identifier is 2, include 1 byte type,
731 * and can not be larger than the length of options
733 if (len
>= 1 && len
< 312 - (e
- options
) - 1) {
736 memcpy(e
, dhcp_client_identifier
, len
+ 1);
741 *e
++ = 255; /* End of the list */
744 #endif /* IPCONFIG_DHCP */
746 static void __init
ic_bootp_init_ext(u8
*e
)
748 memcpy(e
, ic_bootp_cookie
, 4); /* RFC1048 Magic Cookie */
750 *e
++ = 1; /* Subnet mask request */
753 *e
++ = 3; /* Default gateway request */
756 *e
++ = 5; /* Name server request */
759 *e
++ = 12; /* Host name request */
762 *e
++ = 40; /* NIS Domain name request */
765 *e
++ = 17; /* Boot path */
769 *e
++ = 57; /* set extension buffer size for reply */
771 *e
++ = 1; /* 128+236+8+20+14, see dhcpd sources */
774 *e
++ = 255; /* End of the list */
779 * Initialize the DHCP/BOOTP mechanism.
781 static inline void __init
ic_bootp_init(void)
783 ic_nameservers_predef();
785 dev_add_pack(&bootp_packet_type
);
790 * DHCP/BOOTP cleanup.
792 static inline void __init
ic_bootp_cleanup(void)
794 dev_remove_pack(&bootp_packet_type
);
799 * Send DHCP/BOOTP request to single interface.
801 static void __init
ic_bootp_send_if(struct ic_device
*d
, unsigned long jiffies_diff
)
803 struct net_device
*dev
= d
->dev
;
807 int hlen
= LL_RESERVED_SPACE(dev
);
808 int tlen
= dev
->needed_tailroom
;
810 /* Allocate packet */
811 skb
= alloc_skb(sizeof(struct bootp_pkt
) + hlen
+ tlen
+ 15,
815 skb_reserve(skb
, hlen
);
816 b
= (struct bootp_pkt
*) skb_put(skb
, sizeof(struct bootp_pkt
));
817 memset(b
, 0, sizeof(struct bootp_pkt
));
819 /* Construct IP header */
820 skb_reset_network_header(skb
);
824 h
->tot_len
= htons(sizeof(struct bootp_pkt
));
825 h
->frag_off
= htons(IP_DF
);
827 h
->protocol
= IPPROTO_UDP
;
828 h
->daddr
= htonl(INADDR_BROADCAST
);
829 h
->check
= ip_fast_csum((unsigned char *) h
, h
->ihl
);
831 /* Construct UDP header */
832 b
->udph
.source
= htons(68);
833 b
->udph
.dest
= htons(67);
834 b
->udph
.len
= htons(sizeof(struct bootp_pkt
) - sizeof(struct iphdr
));
835 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
837 /* Construct DHCP/BOOTP header */
838 b
->op
= BOOTP_REQUEST
;
839 if (dev
->type
< 256) /* check for false types */
840 b
->htype
= dev
->type
;
841 else if (dev
->type
== ARPHRD_FDDI
)
842 b
->htype
= ARPHRD_ETHER
;
844 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev
->type
,
846 b
->htype
= dev
->type
; /* can cause undefined behavior */
849 /* server_ip and your_ip address are both already zero per RFC2131 */
850 b
->hlen
= dev
->addr_len
;
851 memcpy(b
->hw_addr
, dev
->dev_addr
, dev
->addr_len
);
852 b
->secs
= htons(jiffies_diff
/ HZ
);
855 /* add DHCP options or BOOTP extensions */
857 if (ic_proto_enabled
& IC_USE_DHCP
)
858 ic_dhcp_init_options(b
->exten
, d
);
861 ic_bootp_init_ext(b
->exten
);
863 /* Chain packet down the line... */
865 skb
->protocol
= htons(ETH_P_IP
);
866 if (dev_hard_header(skb
, dev
, ntohs(skb
->protocol
),
867 dev
->broadcast
, dev
->dev_addr
, skb
->len
) < 0) {
873 if (dev_queue_xmit(skb
) < 0)
879 * Copy BOOTP-supplied string if not already set.
881 static int __init
ic_bootp_string(char *dest
, char *src
, int len
, int max
)
887 memcpy(dest
, src
, len
);
894 * Process BOOTP extensions.
896 static void __init
ic_do_bootp_ext(u8
*ext
)
904 pr_debug("DHCP/BOOTP: Got extension %d:", *ext
);
905 for (c
=ext
+2; c
<ext
+2+ext
[1]; c
++)
906 pr_debug(" %02x", *c
);
910 case 1: /* Subnet mask */
911 if (ic_netmask
== NONE
)
912 memcpy(&ic_netmask
, ext
+1, 4);
914 case 3: /* Default gateway */
915 if (ic_gateway
== NONE
)
916 memcpy(&ic_gateway
, ext
+1, 4);
918 case 6: /* DNS server */
920 if (servers
> CONF_NAMESERVERS_MAX
)
921 servers
= CONF_NAMESERVERS_MAX
;
922 for (i
= 0; i
< servers
; i
++) {
923 if (ic_nameservers
[i
] == NONE
)
924 memcpy(&ic_nameservers
[i
], ext
+1+4*i
, 4);
927 case 12: /* Host name */
928 ic_bootp_string(utsname()->nodename
, ext
+1, *ext
,
930 ic_host_name_set
= 1;
932 case 15: /* Domain name (DNS) */
933 ic_bootp_string(ic_domain
, ext
+1, *ext
, sizeof(ic_domain
));
935 case 17: /* Root path */
936 if (!root_server_path
[0])
937 ic_bootp_string(root_server_path
, ext
+1, *ext
,
938 sizeof(root_server_path
));
940 case 26: /* Interface MTU */
941 memcpy(&mtu
, ext
+1, sizeof(mtu
));
942 ic_dev_mtu
= ntohs(mtu
);
944 case 40: /* NIS Domain name (_not_ DNS) */
945 ic_bootp_string(utsname()->domainname
, ext
+1, *ext
,
953 * Receive BOOTP reply.
955 static int __init
ic_bootp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
)
962 if (!net_eq(dev_net(dev
), &init_net
))
965 /* Perform verifications before taking the lock. */
966 if (skb
->pkt_type
== PACKET_OTHERHOST
)
969 skb
= skb_share_check(skb
, GFP_ATOMIC
);
973 if (!pskb_may_pull(skb
,
974 sizeof(struct iphdr
) +
975 sizeof(struct udphdr
)))
978 b
= (struct bootp_pkt
*)skb_network_header(skb
);
981 if (h
->ihl
!= 5 || h
->version
!= 4 || h
->protocol
!= IPPROTO_UDP
)
984 /* Fragments are not supported */
985 if (ip_is_fragment(h
)) {
986 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
990 if (skb
->len
< ntohs(h
->tot_len
))
993 if (ip_fast_csum((char *) h
, h
->ihl
))
996 if (b
->udph
.source
!= htons(67) || b
->udph
.dest
!= htons(68))
999 if (ntohs(h
->tot_len
) < ntohs(b
->udph
.len
) + sizeof(struct iphdr
))
1002 len
= ntohs(b
->udph
.len
) - sizeof(struct udphdr
);
1003 ext_len
= len
- (sizeof(*b
) -
1004 sizeof(struct iphdr
) -
1005 sizeof(struct udphdr
) -
1010 /* Ok the front looks good, make sure we can get at the rest. */
1011 if (!pskb_may_pull(skb
, skb
->len
))
1014 b
= (struct bootp_pkt
*)skb_network_header(skb
);
1017 /* One reply at a time, please. */
1018 spin_lock(&ic_recv_lock
);
1020 /* If we already have a reply, just drop the packet */
1024 /* Find the ic_device that the packet arrived on */
1026 while (d
&& d
->dev
!= dev
)
1029 goto drop_unlock
; /* should never happen */
1031 /* Is it a reply to our BOOTP request? */
1032 if (b
->op
!= BOOTP_REPLY
||
1034 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1035 d
->dev
->name
, b
->op
, b
->xid
);
1039 /* Parse extensions */
1041 !memcmp(b
->exten
, ic_bootp_cookie
, 4)) { /* Check magic cookie */
1042 u8
*end
= (u8
*) b
+ ntohs(b
->iph
.tot_len
);
1045 #ifdef IPCONFIG_DHCP
1046 if (ic_proto_enabled
& IC_USE_DHCP
) {
1047 __be32 server_id
= NONE
;
1051 while (ext
< end
&& *ext
!= 0xff) {
1053 if (*opt
== 0) /* Padding */
1059 case 53: /* Message type */
1063 case 54: /* Server ID (IP address) */
1065 memcpy(&server_id
, opt
+ 2, 4);
1070 pr_debug("DHCP: Got message type %d (%s)\n", mt
, d
->dev
->name
);
1074 /* While in the process of accepting one offer,
1075 * ignore all others.
1077 if (ic_myaddr
!= NONE
)
1080 /* Let's accept that offer. */
1081 ic_myaddr
= b
->your_ip
;
1082 ic_servaddr
= server_id
;
1083 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1084 &ic_myaddr
, &b
->iph
.saddr
);
1085 /* The DHCP indicated server address takes
1086 * precedence over the bootp header one if
1087 * they are different.
1089 if ((server_id
!= NONE
) &&
1090 (b
->server_ip
!= server_id
))
1091 b
->server_ip
= ic_servaddr
;
1095 if (memcmp(dev
->dev_addr
, b
->hw_addr
, dev
->addr_len
) != 0)
1102 /* Urque. Forget it*/
1108 ic_dhcp_msgtype
= mt
;
1111 #endif /* IPCONFIG_DHCP */
1114 while (ext
< end
&& *ext
!= 0xff) {
1116 if (*opt
== 0) /* Padding */
1120 ic_do_bootp_ext(opt
);
1124 /* We have a winner! */
1126 ic_myaddr
= b
->your_ip
;
1127 ic_servaddr
= b
->server_ip
;
1128 ic_addrservaddr
= b
->iph
.saddr
;
1129 if (ic_gateway
== NONE
&& b
->relay_ip
)
1130 ic_gateway
= b
->relay_ip
;
1131 if (ic_nameservers
[0] == NONE
)
1132 ic_nameservers
[0] = ic_servaddr
;
1133 ic_got_reply
= IC_BOOTP
;
1136 /* Show's over. Nothing to see here. */
1137 spin_unlock(&ic_recv_lock
);
1140 /* Throw the packet out. */
1151 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1154 #ifdef IPCONFIG_DYNAMIC
1156 static int __init
ic_dynamic(void)
1159 struct ic_device
*d
;
1160 unsigned long start_jiffies
, timeout
, jiff
;
1161 int do_bootp
= ic_proto_have_if
& IC_BOOTP
;
1162 int do_rarp
= ic_proto_have_if
& IC_RARP
;
1165 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1166 * This routine gets only called when some pieces of information
1167 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1169 if (!ic_proto_enabled
) {
1170 pr_err("IP-Config: Incomplete network configuration information\n");
1174 #ifdef IPCONFIG_BOOTP
1175 if ((ic_proto_enabled
^ ic_proto_have_if
) & IC_BOOTP
)
1176 pr_err("DHCP/BOOTP: No suitable device found\n");
1178 #ifdef IPCONFIG_RARP
1179 if ((ic_proto_enabled
^ ic_proto_have_if
) & IC_RARP
)
1180 pr_err("RARP: No suitable device found\n");
1183 if (!ic_proto_have_if
)
1184 /* Error message already printed */
1190 #ifdef IPCONFIG_BOOTP
1194 #ifdef IPCONFIG_RARP
1200 * Send requests and wait, until we get an answer. This loop
1201 * seems to be a terrible waste of CPU time, but actually there is
1202 * only one process running at all, so we don't need to use any
1203 * scheduler functions.
1204 * [Actually we could now, but the nothing else running note still
1207 pr_notice("Sending %s%s%s requests .",
1209 ? ((ic_proto_enabled
& IC_USE_DHCP
) ? "DHCP" : "BOOTP") : "",
1210 (do_bootp
&& do_rarp
) ? " and " : "",
1211 do_rarp
? "RARP" : "");
1213 start_jiffies
= jiffies
;
1215 retries
= CONF_SEND_RETRIES
;
1216 get_random_bytes(&timeout
, sizeof(timeout
));
1217 timeout
= CONF_BASE_TIMEOUT
+ (timeout
% (unsigned int) CONF_TIMEOUT_RANDOM
);
1219 #ifdef IPCONFIG_BOOTP
1220 if (do_bootp
&& (d
->able
& IC_BOOTP
))
1221 ic_bootp_send_if(d
, jiffies
- start_jiffies
);
1223 #ifdef IPCONFIG_RARP
1224 if (do_rarp
&& (d
->able
& IC_RARP
))
1229 jiff
= jiffies
+ timeout
;
1230 while (time_before(jiffies
, jiff
) && !ic_got_reply
)
1231 schedule_timeout_uninterruptible(1);
1233 #ifdef IPCONFIG_DHCP
1234 /* DHCP isn't done until we get a DHCPACK. */
1235 if ((ic_got_reply
& IC_BOOTP
) &&
1236 (ic_proto_enabled
& IC_USE_DHCP
) &&
1237 ic_dhcp_msgtype
!= DHCPACK
) {
1239 /* continue on device that got the reply */
1244 #endif /* IPCONFIG_DHCP */
1255 pr_cont(" timed out!\n");
1261 timeout
= timeout CONF_TIMEOUT_MULT
;
1262 if (timeout
> CONF_TIMEOUT_MAX
)
1263 timeout
= CONF_TIMEOUT_MAX
;
1268 #ifdef IPCONFIG_BOOTP
1272 #ifdef IPCONFIG_RARP
1277 if (!ic_got_reply
) {
1282 pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1283 ((ic_got_reply
& IC_RARP
) ? "RARP"
1284 : (ic_proto_enabled
& IC_USE_DHCP
) ? "DHCP" : "BOOTP"),
1285 &ic_addrservaddr
, &ic_myaddr
);
1290 #endif /* IPCONFIG_DYNAMIC */
1292 #ifdef CONFIG_PROC_FS
1294 static int pnp_seq_show(struct seq_file
*seq
, void *v
)
1298 if (ic_proto_used
& IC_PROTO
)
1299 seq_printf(seq
, "#PROTO: %s\n",
1300 (ic_proto_used
& IC_RARP
) ? "RARP"
1301 : (ic_proto_used
& IC_USE_DHCP
) ? "DHCP" : "BOOTP");
1303 seq_puts(seq
, "#MANUAL\n");
1307 "domain %s\n", ic_domain
);
1308 for (i
= 0; i
< CONF_NAMESERVERS_MAX
; i
++) {
1309 if (ic_nameservers
[i
] != NONE
)
1310 seq_printf(seq
, "nameserver %pI4\n",
1311 &ic_nameservers
[i
]);
1313 if (ic_servaddr
!= NONE
)
1314 seq_printf(seq
, "bootserver %pI4\n",
1319 static int pnp_seq_open(struct inode
*indoe
, struct file
*file
)
1321 return single_open(file
, pnp_seq_show
, NULL
);
1324 static const struct file_operations pnp_seq_fops
= {
1325 .owner
= THIS_MODULE
,
1326 .open
= pnp_seq_open
,
1328 .llseek
= seq_lseek
,
1329 .release
= single_release
,
1331 #endif /* CONFIG_PROC_FS */
1334 * Extract IP address from the parameter string if needed. Note that we
1335 * need to have root_server_addr set _before_ IPConfig gets called as it
1338 __be32 __init
root_nfs_parse_addr(char *name
)
1345 while (octets
< 4) {
1346 while (*cp
>= '0' && *cp
<= '9')
1348 if (cp
== cq
|| cp
- cq
> 3)
1350 if (*cp
== '.' || octets
== 3)
1356 if (octets
== 4 && (*cp
== ':' || *cp
== '\0')) {
1359 addr
= in_aton(name
);
1360 memmove(name
, cp
, strlen(cp
) + 1);
1367 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1369 static int __init
wait_for_devices(void)
1373 for (i
= 0; i
< DEVICE_WAIT_MAX
; i
++) {
1374 struct net_device
*dev
;
1378 for_each_netdev(&init_net
, dev
) {
1379 if (ic_is_init_dev(dev
)) {
1393 * IP Autoconfig dispatcher.
1396 static int __init
ip_auto_config(void)
1399 #ifdef IPCONFIG_DYNAMIC
1400 int retries
= CONF_OPEN_RETRIES
;
1405 #ifdef CONFIG_PROC_FS
1406 proc_create("pnp", S_IRUGO
, init_net
.proc_net
, &pnp_seq_fops
);
1407 #endif /* CONFIG_PROC_FS */
1412 pr_debug("IP-Config: Entered.\n");
1413 #ifdef IPCONFIG_DYNAMIC
1416 /* Wait for devices to appear */
1417 err
= wait_for_devices();
1421 /* Setup all network devices */
1422 err
= ic_open_devs();
1426 /* Give drivers a chance to settle */
1427 msleep(CONF_POST_OPEN
);
1430 * If the config information is insufficient (e.g., our IP address or
1431 * IP address of the boot server is missing or we have multiple network
1432 * interfaces and no default was set), use BOOTP or RARP to get the
1435 if (ic_myaddr
== NONE
||
1436 #ifdef CONFIG_ROOT_NFS
1437 (root_server_addr
== NONE
&&
1438 ic_servaddr
== NONE
&&
1439 ROOT_DEV
== Root_NFS
) ||
1441 ic_first_dev
->next
) {
1442 #ifdef IPCONFIG_DYNAMIC
1443 if (ic_dynamic() < 0) {
1447 * I don't know why, but sometimes the
1448 * eepro100 driver (at least) gets upset and
1449 * doesn't work the first time it's opened.
1450 * But then if you close it and reopen it, it
1451 * works just fine. So we need to try that at
1452 * least once before giving up.
1454 * Also, if the root will be NFS-mounted, we
1455 * have nowhere to go if DHCP fails. So we
1456 * just have to keep trying forever.
1460 #ifdef CONFIG_ROOT_NFS
1461 if (ROOT_DEV
== Root_NFS
) {
1462 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1468 pr_err("IP-Config: Reopening network devices...\n");
1472 /* Oh, well. At least we tried. */
1473 pr_err("IP-Config: Auto-configuration of network failed\n");
1476 #else /* !DYNAMIC */
1477 pr_err("IP-Config: Incomplete network configuration information\n");
1480 #endif /* IPCONFIG_DYNAMIC */
1482 /* Device selected manually or only one device -> use it */
1483 ic_dev
= ic_first_dev
;
1486 addr
= root_nfs_parse_addr(root_server_path
);
1487 if (root_server_addr
== NONE
)
1488 root_server_addr
= addr
;
1491 * Use defaults wherever applicable.
1493 if (ic_defaults() < 0)
1497 * Record which protocol was actually used.
1499 #ifdef IPCONFIG_DYNAMIC
1500 ic_proto_used
= ic_got_reply
| (ic_proto_enabled
& IC_USE_DHCP
);
1503 #ifndef IPCONFIG_SILENT
1505 * Clue in the operator.
1507 pr_info("IP-Config: Complete:\n");
1509 pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1510 ic_dev
->dev
->name
, ic_dev
->dev
->addr_len
, ic_dev
->dev
->dev_addr
,
1511 &ic_myaddr
, &ic_netmask
, &ic_gateway
);
1512 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1513 utsname()->nodename
, ic_domain
, utsname()->domainname
);
1514 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1515 &ic_servaddr
, &root_server_addr
, root_server_path
);
1517 pr_cont(", mtu=%d", ic_dev_mtu
);
1518 for (i
= 0; i
< CONF_NAMESERVERS_MAX
; i
++)
1519 if (ic_nameservers
[i
] != NONE
) {
1520 pr_cont(" nameserver%u=%pI4",
1521 i
, &ic_nameservers
[i
]);
1524 for (i
++; i
< CONF_NAMESERVERS_MAX
; i
++)
1525 if (ic_nameservers
[i
] != NONE
)
1526 pr_cont(", nameserver%u=%pI4", i
, &ic_nameservers
[i
]);
1528 #endif /* !SILENT */
1531 * Close all network devices except the device we've
1532 * autoconfigured and set up routes.
1534 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1544 late_initcall(ip_auto_config
);
1548 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1549 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1551 static int __init
ic_proto_name(char *name
)
1553 if (!strcmp(name
, "on") || !strcmp(name
, "any")) {
1556 if (!strcmp(name
, "off") || !strcmp(name
, "none")) {
1559 #ifdef CONFIG_IP_PNP_DHCP
1560 else if (!strncmp(name
, "dhcp", 4)) {
1563 ic_proto_enabled
&= ~IC_RARP
;
1564 client_id
= strstr(name
, "dhcp,");
1568 client_id
= client_id
+ 5;
1569 v
= strchr(client_id
, ',');
1573 if (kstrtou8(client_id
, 0, dhcp_client_identifier
))
1574 pr_debug("DHCP: Invalid client identifier type\n");
1575 strncpy(dhcp_client_identifier
+ 1, v
+ 1, 251);
1581 #ifdef CONFIG_IP_PNP_BOOTP
1582 else if (!strcmp(name
, "bootp")) {
1583 ic_proto_enabled
&= ~(IC_RARP
| IC_USE_DHCP
);
1587 #ifdef CONFIG_IP_PNP_RARP
1588 else if (!strcmp(name
, "rarp")) {
1589 ic_proto_enabled
&= ~(IC_BOOTP
| IC_USE_DHCP
);
1593 #ifdef IPCONFIG_DYNAMIC
1594 else if (!strcmp(name
, "both")) {
1595 ic_proto_enabled
&= ~IC_USE_DHCP
; /* backward compat :-( */
1602 static int __init
ip_auto_config_setup(char *addrs
)
1607 ic_set_manually
= 1;
1611 * If any dhcp, bootp etc options are set, leave autoconfig on
1612 * and skip the below static IP processing.
1614 if (ic_proto_name(addrs
))
1617 /* If no static IP is given, turn off autoconfig and bail. */
1619 strcmp(addrs
, "off") == 0 ||
1620 strcmp(addrs
, "none") == 0) {
1625 ic_nameservers_predef();
1627 /* Parse string for static IP assignment. */
1630 if ((cp
= strchr(ip
, ':')))
1632 if (strlen(ip
) > 0) {
1633 pr_debug("IP-Config: Parameter #%d: `%s'\n", num
, ip
);
1636 if ((ic_myaddr
= in_aton(ip
)) == ANY
)
1640 if ((ic_servaddr
= in_aton(ip
)) == ANY
)
1644 if ((ic_gateway
= in_aton(ip
)) == ANY
)
1648 if ((ic_netmask
= in_aton(ip
)) == ANY
)
1652 if ((dp
= strchr(ip
, '.'))) {
1654 strlcpy(utsname()->domainname
, dp
,
1655 sizeof(utsname()->domainname
));
1657 strlcpy(utsname()->nodename
, ip
,
1658 sizeof(utsname()->nodename
));
1659 ic_host_name_set
= 1;
1662 strlcpy(user_dev_name
, ip
, sizeof(user_dev_name
));
1665 if (ic_proto_name(ip
) == 0 &&
1666 ic_myaddr
== NONE
) {
1671 if (CONF_NAMESERVERS_MAX
>= 1) {
1672 ic_nameservers
[0] = in_aton(ip
);
1673 if (ic_nameservers
[0] == ANY
)
1674 ic_nameservers
[0] = NONE
;
1678 if (CONF_NAMESERVERS_MAX
>= 2) {
1679 ic_nameservers
[1] = in_aton(ip
);
1680 if (ic_nameservers
[1] == ANY
)
1681 ic_nameservers
[1] = NONE
;
1692 __setup("ip=", ip_auto_config_setup
);
1694 static int __init
nfsaddrs_config_setup(char *addrs
)
1696 return ip_auto_config_setup(addrs
);
1698 __setup("nfsaddrs=", nfsaddrs_config_setup
);
1700 static int __init
vendor_class_identifier_setup(char *addrs
)
1702 if (strlcpy(vendor_class_identifier
, addrs
,
1703 sizeof(vendor_class_identifier
))
1704 >= sizeof(vendor_class_identifier
))
1705 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1706 vendor_class_identifier
);
1709 __setup("dhcpclass=", vendor_class_identifier_setup
);